In his latest plot for world domination, the Yellow Claw captured six very powerful mutants possessing reality altering powers. He subjugated these mutants to his will using his power of hypnotism and set them to causing chaos throughout California. Jimmy Woo received a note from the Claw's grand-niece Suwan and follows its instructions, flying a jet alone into the Mojave desert. She shows him the way to the Claw's secret headquarters, but Jimmy's gun turns into a set of handcuffs because of the mutant's powers. The Claw then shows Jimmy the mutants who he plans to use to take over the world. Unbeknown to him, however, Suwan makes her way over to a large gong and bangs it, breaking the Yellow Claw's control and causing the mutants to come to. The mutants then use their powers to escape the Claw's clutches and teleport out of the secret base in a giant flash of light. The Claw, however, escapes aboard a plane with Suwan before Jimmy can capture him.

Jimmy Woo of the FBI is in San Francisco searching for traces of Yellow Claw and spots a suspicious looking elderly couple boarding the S.S. Aloha when he notices that the "elderly woman" is walking in the way of someone much younger. Woo gets permission from his superiors to board the ship and goes undercover as a steward and learns from the captain that the elderly couple are in cabin 361. However they find that checking out the passengers is difficult when they have not left their rooms and have had food dropped off at their door.

Inside cabin 361, Jimmy's fears prove correct as Yellow Claw, his agent Karl von Horstbadden are in the cabin and keeping Yellow Claw's daughter Suwan sedated so that she does not tip off Jimmy Woo to their current whereabouts. Yellow Claw however, exhibiting telepathic abilities detect Woo is coming to snoop on them. When Woo comes pretending to deliver a meal to their room, Yellow Claw invites him in and doffs his disguise. With Woo at gun point, Yellow Claw shows off the images in his crystal ball and revealing his plans. He tells Woo that he intends to steal secret plans from two American diplomats from eastern countries in order to steal the secret plans they are bringing with them.

With Woo as a prisoner, Yellow Claw initiates his plans, sending Karl to take the diplomats prisoner and steal their plans. Yellow Claw then radios his communist allies to have a sub meet them at sea. Yellow Claw then forces Jimmy to carry Suwan out with them as they prepare to jump overboard, but Woo uses a moment to slam into an alarm bell. With everyone on board in a panic, Yellow Claw pulls a gun on Woo and takes Suwan and dives overboard with Karl without the plans and escapes.

Acting on a tip from Suwan, Jimmy Woo goes to a west coast experimental aircraft testing field where he foils one of Yellow Claw's plots to destroy new aircraft with compact explosives. Jimmy's superior asks Jimmy to try and use Suwan to lure Yellow Claw into a trap, Woo agrees despite his reservations over betraying Suwan's trust.

Jimmy then calls Suwan and meets with her at Ching's Tea Room but she soon leaves abruptly. Jimmy then uses her departure to follow after her, and witnesses her triggering a secret passage into Yellow Claw's underground lair. Jimmy follows after her and reveals his presence to Yellow Claw, Karl and Suwan. Yellow Claw reveals that he orchestrated things to lure Jimmy into a trap. Yellow Claw then has his minion Hamud who places Woo in a clear bubble and he is ejected out into the ocean while Yellow Claw and his minions effect their escape, evading capture once again.

Colonel Carver of the US Military meets with Jimmy Woo of the FBI to discuss reports that Temujai the Conqueror, a legend among the people of Asia, who has apparently been sighted in the Mayla jungles. Jimmy is sent out to investigate this unaware that he is being watched by Yellow Claw and his minion Kharion Krowe, who control Temujai and hope to use it to take over the world and kill Jimmy Woo, despite the protests of Yellow Claw's niece Suwan.

When Jimmy arrives via helicopter the next day, Temujai captures the helecopter, prompting Jimmy to abandon it and falls right into the hands of Yellow Claw and his minions who takes Jimmy and his pilot prisoner. They are tossed in a jail cell with another prisoner, whom Jimmy recognizes as Professor Knute Linstrom a world famous inventor. Linstrom explains that Yellow Claw kidnapped him in order to exploit his "Flexus" formula, a compound that resembles human flesh and that Temujai is merely a giant robot coated in it and controlled by Krowe.

When Yellow Claw attempts to us Temujai to try and convince the local natives to go to war against the rest of the world he is shocked to find that the robot ordering the people to live in peace. When Yellow Claw goes to the cell where he had locked Jimmy Woo he finds Krowe trapped inside. As it turns out Suwan freed Jimmy and the others and they took over the robot. As they escape Jimmy wonders how they can destroy the robot, Linstrom points out that isn't necessary as the Flexus layer disintegrates as it is only stable for a short time.